The present invention relates to a suction nozzle with a rotary brush for a vacuum cleaner and, more particularly to a suction nozzle with a rotary brush for a vacuum cleaner suitable for cleaning a corner at a boundary portion of a surface to be cleaned such as the intersection between a wall and a floor.
In a conventional suction nozzle with a rotary brush for a vacuum cleaner, a flexible member is provided at the vicinity of a front edge of a suction opening formed in a suction nozzle main body as shown in, for example Japanese Patent Laid-Open No. 120824/1980.
This flexible member of the suction nozzle main body is projected to a position lower than a bottom face of the suction nozzle main body relative to the floor surface. The flexible member completely covers a clearance between the floor surface and the bottom face of the suction nozzle main body. The clearance is formed by the wheels attached at the bottom face of the suction nozzle main body.
The flexible member is caused to bend toward an inner portion of the suction nozzle main body by the suction force. The bending of the flexible member creates a small clearance between a lower end of the flexible member and the floor surface. When the small clearance is created the suction surface. When the small clearance is created the suction force into the suction nozzle main body is made weaker.
A lip shaped flexible member of a suction nozzle for a vacuum cleaner having no rotary brush has been known in, for example Japanese Utility Model Laid-Open No. 112159/1977, in which the flexible member is formed integrally with a bumper provided on an outer peripheral portion of the suction nozzle main body.
This flexible member is projected to a position lower than the bottom face of the suction nozzle main body. The flexible member may also be hung from the bumper so as to cover the lower portion of the front wall of the suction nozzle main body. The flexible member provides an inlet portion for the small space between the floor surface and the suction nozzle main body.
In the above stated former Japanese Patent Laid-Open No. 120824/1980, when the suction nozzle main body is moved with regard to the surface to be cleaned such as a floor surface in the forward direction, large size solid dust particles such as rice pellets, candy dust or peanuts are swept in the forward direction by the flexible member, which is projected to a position lower than the bottom face of the suction nozzle main body. Even though a rotary brush rotated by an electric motor is provided along with the suction force generated by the vacuum, it is still difficult to suck large size solid dust particles into the suction nozzle main body through the suction opening.
In particular, at the corners formed by intersections of the floor surface with the walls, large size solid dust particles being swept by the flexible member remain in the corners. Therefore there is a defect that the cleaning of the corners cannot be carried out thoroughly.
Further, in case of the cleaning of a carpet, friction resistance is large between the flexible member and the carpet. Still further since the air flowing into the suction opening of the suction nozzle main body is decreased and the negative pressure in the suction opening is increased, there is a defect that ease of movement of the suction nozzle main body is reduced being that it is now necessary to use an increased amount of force to move the suction nozzle main body.
In the above stated latter Japanese Utility Model Laid-Open No. 112159/1987, the lip shaped flexible member is projected to a position lower than the bottom face of the suction nozzle main body. Similar to the above stated Japanese Patent Laid-Open No. 120824/1980, the cleaning of large size solid dust particles cannot be carried out thoroughly and ease of movement of the suction nozzle main body is reduced.
In the above stated Japanese Utility Model Laid-Open No. 112159/1987, since the lip shaped flexible member formed integrally with the bumper is projected to a position lower than the bottom face of the suction nozzle main body, it is necessary to exchange the flexible member periodically with a new flexible member, because the lip shaped flexible member contacts the surface to be cleaned thereby subjecting the flexible member to wear. There is also a defect that it is necessary to exchange the bumper at the same time during the exchange of the flexible member since they are integrally formed.
The bumper is required to be made of a soft material and the lip shaped flexible member is required to be made of a material having some degree of hardness. However, since the bumper and the lip shaped flexible member are made integrally, there is a defect that both requirements cannot satisfied at the same time.
The suction nozzle main body is provided with a curved coupling turning portion in which the connection portion for an extension pipe is capable of turning in up and down directions and also in right and left directions. Electric power is supplied to the driving source of the rotary brush through the curved coupling turning portion. Due to the expected turning of the curved coupling turning portion, it is difficult to obtain a good electric connection for supplying electric power to the driving source.
There has been disclosed an electric power supply wiring structure for a power source line in a vacuum cleaner wherein the power source line is installed inside the base and extension pipe. This structure further provides that the power source line for the curved coupling turning portion be installed outside of the curved coupling turning portion. The power source line from outside of the curved coupling turning portion is then lead into the suction nozzle main body.
Further, there has been disclosed another electric power supply wiring structure for a power source line in a vacuum cleaner, in which the power source line is installed inside the hose and extension pipe. However, the electric wiring connection portion turns in only the up and down directions. Accordingly, there appears no electric power supply wiring structure for the vacuum cleaner in which the electric wiring connection portion can turn in all directions.
Since the conventional power source line is disposed outside of the curved coupling turning portion, when the suction nozzle main body is moved under a portion of furniture or a desk, movement of the suction main body may become obstructed by the power source line becoming caught by the furniture. If a large amount of force is applied to the power source line caught by the furniture the power source line is weakened thereby. Thus, the outside installation of the power source line may shorten the life of the power source line.
Further, in the conventional inside installation of the power source line, the turning of the curved coupling turning portion in only the up and down directions limits the use of the suction nozzle main body.